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<head><meta charset="utf-8"><title>diagnostic #82479 · t-compiler/wg-nll · Zulip Chat Archive</title></head>
<h2>Stream: <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/index.html">t-compiler/wg-nll</a></h2>
<h3>Topic: <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html">diagnostic #82479</a></h3>

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<a name="229554314"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229554314" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229554314">(Mar 09 2021 at 21:08)</a>:</h4>
<p>Hey <span class="user-mention" data-user-id="116118">@Matthew Jasper</span> or <span class="user-mention" data-user-id="119031">@Esteban Küber</span> -- <span class="user-mention" data-user-id="392671">@Kshitij</span> was expressing some interest to me in fixing <a href="https://github.com/rust-lang/rust/issues/82479">#82479</a>.</p>



<a name="229554342"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229554342" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229554342">(Mar 09 2021 at 21:09)</a>:</h4>
<p>I thought one of you might be interested in mentoring them in that code, or maybe have some ideas of folks who might be?</p>



<a name="229554355"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229554355" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229554355">(Mar 09 2021 at 21:09)</a>:</h4>
<p><span class="user-mention" data-user-id="116107">@davidtwco</span> might be another candidate :)</p>



<a name="229554410"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229554410" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> nikomatsakis <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229554410">(Mar 09 2021 at 21:09)</a>:</h4>
<p>my read from the issue is that the error message is correct but misleading</p>



<a name="229554791"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229554791" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Esteban Küber <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229554791">(Mar 09 2021 at 21:11)</a>:</h4>
<p>I'm more than happy to help them, but until friday my cycles are all taken up</p>



<a name="229554797"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229554797" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229554797">(Mar 09 2021 at 21:11)</a>:</h4>
<p>Yes, this is kind of difficult because borrowck is deliberately not computing enough information here for perf reasons</p>



<a name="229554921"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229554921" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Matthew Jasper <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229554921">(Mar 09 2021 at 21:12)</a>:</h4>
<p>It's maybe possible to heuristic our way to a better error though, rustc like doing that.</p>



<a name="229555093"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229555093" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Esteban Küber <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229555093">(Mar 09 2021 at 21:13)</a>:</h4>
<p>Yeah, we can probably special-case when this happens on return expressions</p>



<a name="229555217"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229555217" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Esteban Küber <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229555217">(Mar 09 2021 at 21:14)</a>:</h4>
<p>This also makes me sad that I haven't spent time pushing for partial self borrows :)</p>



<a name="229555410"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229555410" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Kshitij <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229555410">(Mar 09 2021 at 21:15)</a>:</h4>
<p>Are issues like these taken up as part of some sprints you guys have? And when non-member contributors work on them, what are the expectations for turnaround?</p>



<a name="229556742"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229556742" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Esteban Küber <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229556742">(Mar 09 2021 at 21:25)</a>:</h4>
<p>First come/first serve, we try to help people as they work, having at least a draft PR helps to provide inline comments. There's no timing constraints except for fixes for stable to stable regressions, which is usually taken up by team members.</p>



<a name="229557259"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229557259" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Kshitij <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229557259">(Mar 09 2021 at 21:29)</a>:</h4>
<p>Sounds good, thanks! I'd at least like to give it a shot and would be free to sync up Friday evening or after, if you have time?</p>



<a name="229567328"></a>
<h4><a href="https://rust-lang.zulipchat.com#narrow/stream/122657-t-compiler/wg-nll/topic/diagnostic%20%2382479/near/229567328" class="zl"><img src="https://rust-lang.github.io/zulip_archive/assets/img/zulip.svg" alt="view this post on Zulip" style="width:20px;height:20px;"></a> Esteban Küber <a href="https://rust-lang.github.io/zulip_archive/stream/122657-t-compiler/wg-nll/topic/diagnostic.20.2382479.html#229567328">(Mar 09 2021 at 22:26)</a>:</h4>
<p>Feel free to ping me here in zulip, @estebank on github or @ekuber on twitter</p>



<hr><p>Last updated: Aug 07 2021 at 22:04 UTC</p>
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